1. Technical Field
The present disclosure relates to backlight modules and liquid crystal displays (LCDs), and particularly to a backlight module having a light concentrating and scattering structure and an LCD using the same.
2. Description of Related Art
Liquid crystal devices (LCDs) are commonly used as displays for compact electronic apparatuses. This is because LCDs not only provide good quality images using little power, but are also conveniently thin. Because liquid crystal in an LCD does not emit any light itself, the LCD requires a light source to clearly and sharply display text and images. Therefore, LCDs typically require a backlight module.
Referring to FIG. 8, a typical backlight module 10 includes a light guide plate 100 and two light emitting diodes (LEDs) 110. The light guide plate 100 includes a light emitting surface 104 and a light incident surface 102 perpendicular to the light emitting surface 104. The LEDs 110 are disposed adjacent to the light incident surface 102. The light guide plate 100 transforms the point light emitting from the LEDs 110 into a surface light.
However, light beams emitting from each LED 110 have a limited divergence angle ψ. Thus, a darkened area 108 is formed in the light guide plate 100 in a region corresponding to the midpoint between the two LEDs 110. Therefore, the backlight module 10 cannot produce uniform brightness over the whole light emitting surface 104.
What is needed, therefore, is a backlight module that can overcome the above-described deficiencies. What is also needed is an LCD using the backlight module.